From January 1990 through December 1992, 1,585 preoperative wire local
ization procedures of occult breast lesions were performed at the auth
ors' institution. Of these, 739 (47%) were masses, and ultrasound (US)
guidance was performed to localize 30 lesions. In five of the 30 lesi
ons, no mass was seen at radiography of the specimen, but US of the sp
ecimen helped confirm complete excision.